Sequenced reactions are used to produce complex molecules, such as those in which both the C—N and C—C bonded moieties are fundamental features. Examples of such complex molecules include, but are not limited to 6-phenanthridinones and their heterocyclic analogs.
Examples of sequenced reactions used to form such products include, but are not limited to, transition metal-catalyzed sequential C—C and C-heteroatom bond forming reactions. This includes amination/intramolecular cyclization reaction sequences for the synthesis of indole derivatives such as 1,3-diphenylindazole; 1,3-di-p-tolylindazole; and 1-phenyl-3-p-methoxy phenyl indazole, and so forth. However, such sequenced reactions are costly and time-consuming as they require multiple catalysts (or catalyst systems) and/or multiple pots. These methods are also not necessarily environmentally friendly as there are typically large amounts of waste products generated.
Other complex molecules produced with sequenced reactions include N,N-diarylaminostilbenes. Known synthetic routes for these compounds begin from aniline and the corresponding aryl halides via a three step process involving an Ullmann, Vilsmeier and Wittig reaction sequence. Alternatively, these reactions can begin with triphenylamine as a starting material via a Vilsmeier, Wittig and palladium-catalyzed arylation reaction series. It is also possible to synthesize trans-4-N,N-diarylaminostilbenes from the corresponding halostilbenes or aminostilbenes using palladium catalyzed amination/arylation reactions. All such methods, however, require multiple catalysts (or catalyst systems) and/or more than one pot.
Thus, what is needed is an efficient and economical way to produce complex molecules, such as those in which both the C—N and C—C bonded moieties are fundamental features.